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Sun YS, Jian YQ, Yang ST, Wang HF, Junisu BA, Chen CY, Lin JM. Epitaxial Growth of Surface Perforations on Parallel Cylinders in Terraced Films of Block Copolymer/Homopolymer Blends. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:7680-7691. [PMID: 38551605 PMCID: PMC11008238 DOI: 10.1021/acs.langmuir.4c00385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/05/2024] [Accepted: 03/12/2024] [Indexed: 04/10/2024]
Abstract
Due to incommensurability between initial thickness and interdomain distance, thermal annealing inevitably produces relief surface terraces (islands and holes) of various morphologies in thin films of block copolymers. We have demonstrated three kinds of surface terraces in blend films: polygrain terraces with diffuse edges, polygrain terraces with step edges, and pseudo-monograin terraces with island coarsening. The three morphologies were obtained by three different thermal histories, respectively. The thermal histories were imposed on blend films, which were prepared by mixing a homopolystyrene (hPS, 6.1 kg/mol) with a weakly segregated, symmetry polystyrene-block poly(methyl methacrylate) (PS-b-PMMA, 42 kg/mol) followed by spin coating. At a given weight-fraction ratio of PS-b-PMMA/hPS = 75/25, the interior of the blend films forms parallel cylinders. Nevertheless, the surface of the blend films is always dominated by a skin layer of perforations, which epitaxially grow on top of parallel cylinders. By oxygen plasma etching at various time intervals to probe interior nanodomains, the epitaxial relationship between surface perforations and parallel cylinders has been identified by a scanning electron microscope.
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Affiliation(s)
- Ya-Sen Sun
- Department
of Chemical Engineering, National Cheng
Kung University, Tainan 701, Taiwan
| | - Yi-Qing Jian
- Department
of Chemical and Materials Engineering, National
Central University, Taoyuan 32001, Taiwan
| | - Shin-Tung Yang
- Department
of Chemical and Materials Engineering, National
Central University, Taoyuan 32001, Taiwan
| | - Hsiao-Fang Wang
- Department
of Chemical and Materials Engineering, National
Central University, Taoyuan 32001, Taiwan
| | - Belda Amelia Junisu
- Department
of Chemical Engineering, National Cheng
Kung University, Tainan 701, Taiwan
| | - Chun-Yu Chen
- National
Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Jhih-Min Lin
- National
Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
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Sun YS, Liao YP, Hung HH, Chiang PH, Su CJ. Molecular-weight effects of a homopolymer on the AB- and ABC-stacks of perforations in block copolymer/homopolymer films. SOFT MATTER 2024; 20:609-620. [PMID: 38131364 DOI: 10.1039/d3sm01249b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
We have demonstrated the molecular-weight effects of adding homopolystyrene (hPS) on the evolution of perforated layers and double gyroids in polystyrene-block-poly(methyl methacrylate)-based films during isothermal annealing. Two homopolystyrenes of 2.8 and 17 kg mol-1 were used. To prepare blend films, PS-b-PMMA and hPSx (x: 2.8 or 17) were mixed at a weight-fraction ratio of 75/25 in toluene and then spin-coated at SiOx/Si. Spin coating inevitably produced films with thick edges at the periphery of the substrate. The structural evolution of the spun films was in situ characterized by grazing incidence small-angle X-ray scattering (GISAXS). The annealed films were then characterized using a scanning electron microscope (SEM). We found that thin middle regions behaved differently from thick beads for the films. The middle of the blend films mainly formed perforated layers with different spatial orders and orientations, depending on the molecular weight of added hPS chains. Hexagonally perforated layers quickly formed at 205 °C for PS-b-PMMA/hPS2.8 films. However, when hPS17 was used instead of hPS2.8, perforated layers formed with defects in PS-b-PMMA/hPS17 films annealed at 205 °C. Annealing at 240 °C improved the spatial order and orientation of perforated layers for a PS-b-PMMA/hPS17 film. Nevertheless, annealing at 240 °C inversely depressed the in-plane spatial order of perforated layers for a PS-b-PMMA/hPS2.8 film. The depression in the in-plane spatial order is ascribed to a dilution effect of added short chains. Compared to the middle regions, the thick beads went through several metastable phases, such as perpendicularly oriented perforated layers and double gyroids.
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Affiliation(s)
- Ya-Sen Sun
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan.
| | - Yin-Ping Liao
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Hsiang-Ho Hung
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Pei-Hsuan Chiang
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Chun-Jen Su
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
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Sun YS, Jian YQ, Yang ST, Chen CY, Lin JM. Morphologies of Surface Perforations and Parallel Cylinders Coexisting in Terraced Films of Block Copolymer/Homopolymer Blends with Oxygen Plasma Etching. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:16284-16293. [PMID: 37934122 DOI: 10.1021/acs.langmuir.3c01784] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
This study has demonstrated how oxygen plasma etching carves surface structures for thin films of polystyrene-block-poly(methyl methacrylate)/homopolystyrene blends. By tuning the weight-fraction ratio, blend films form perforations and cylinders on the SiOx/Si substrate. Since perforations exist only on the free surface and substrate interface, short exposure to oxygen plasma to quickly etch the PMMA component produces distorted hexagonal arrays of nanodots on the free surface. The interior of the blend films forms polygrain micro-structures composed of parallel cylinders with an in-plane random orientation. Oxygen plasma etching imposed on the fractured surfaces results in five morphologies: (i) distorted hexagonal arrays of nanoholes, (ii) layer-by-layer stacks, (iii) zigzag-like arrays, (iv) intertwined rectangular arrays of nanodots and nanoholes, and (v) intertwined parallelogram arrays of nanodots and nanoholes. The morphologies suggest synergic effects of grain orientations, stresses, spatial confinement, local segregation of chains, and etching kinetics on the terraced films with oxygen plasma etching.
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Affiliation(s)
- Ya-Sen Sun
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Yi-Qing Jian
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Shin-Tung Yang
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Chun-Yu Chen
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Jhih-Min Lin
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
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Guo Y. Effect of Film Thickness on the Self-Assembly of CBABC Symmetric Pentablock Terpolymer Melts under 1D Confinement: A Dissipative Particle Dynamic Study. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6862. [PMID: 37959459 PMCID: PMC10648495 DOI: 10.3390/ma16216862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 10/20/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023]
Abstract
The study investigates the impact of film thickness on the phase behavior of pentablock terpolymers, denoted as C3B3A6B3C3, when subjected to wall confinement by utilizing the dissipative particle dynamics method. Phase diagrams were constructed to elucidate how factors such as block-block interaction strength, film thickness, and wall properties affect the self-assembly structures. In cases where the wall exhibits no preference for any of the blocks, lamellae phases with orientations perpendicular to the wall are observed. The order-disorder transition (ODT) temperature is found to be influenced by the interaction between the polymer and the wall in thin confinement scenarios. When the wall displays a preference for specific blocks, the orientation of lamellae structures undergoes variations. Lamellae tend to align parallel to the wall when the wall favors A or C blocks, and they orient perpendicularly when B blocks are favored. Furthermore, the mechanical properties of the lamellae structures are related to the conformations of the polymer chains. Structures where chains predominantly adopt a loop conformation exhibit enhanced elastic properties. The ratio of looping to bridging conformations can be adjusted by altering the film thickness and wall selectivity.
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Affiliation(s)
- Yingying Guo
- School of Science, Qingdao University of Technology, Qingdao 266525, China
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Guo Y, Bai L. Dissipative Particle Dynamics Simulation for the Self-Assembly of Symmetric Pentablock Terpolymers Melts under 1D Confinements. Polymers (Basel) 2023; 15:3982. [PMID: 37836033 PMCID: PMC10575399 DOI: 10.3390/polym15193982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/30/2023] [Accepted: 10/02/2023] [Indexed: 10/15/2023] Open
Abstract
The phase behavior of CBABC pentablock terpolymers confined in thin films is investigated using the Dissipative Particle Dynamic method. Phase diagrams are constructed and used to reveal how chain length (i-block length), block composition and wall selectivity influence the self-assembly structures. Under neutral walls, four categories of morphologies, i.e., perpendicular lamellae, core-shell types of microstructures, complex networks, and half-domain morphologies, are identified with the change in i-block length. Ordered structures are more common at weak polymer-polymer interaction strengths. For polymers of a consistent chain length, when one of the three components has a relatively smaller length, the morphologies transition is sensitive to block composition. With selective walls, parallel lamellae structures are prevalent. Wall selectivity also impacts chain conformations. While a large portion of chains form loop conformations under A-selective walls, more chains adopt bridge conformation when the wall prefers C-blocks. These findings offer insights for designing nanopatterns using symmetric pentablock terpolymers.
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Affiliation(s)
- Yingying Guo
- School of Science, Qingdao University of Technology, Qingdao 266525, China
| | - Linqing Bai
- School of Mechanical and Automotive Engineering, Qingdao University of Technology, Qingdao 266525, China;
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Biodegradable binary blends of poly (butylene succinate) or poly (ε-caprolactone) with poly (butylene succinate-ran-ε-caprolactone)copolymers: Crystallization behavior. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Hong JW, Chang JH, Hung HH, Liao YP, Jian YQ, Chang ICY, Huang TY, Nelson A, Lin IM, Chiang YW, Sun YS. Chain Length Effects of Added Homopolymers on the Phase Behavior in Blend Films of a Symmetric, Weakly Segregated Polystyrene- block-poly(methyl methacrylate). Macromolecules 2022. [DOI: 10.1021/acs.macromol.1c02167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jia-Wen Hong
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Jung-Hong Chang
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Hsiang-Ho Hung
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Yin-Ping Liao
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Yi-Qing Jian
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Iris Ching-Ya Chang
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Tzu-Yen Huang
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Andrew Nelson
- Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - I-Ming Lin
- Department of Materials and Optoelectronic Science, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan
| | - Yeo-Wan Chiang
- Department of Materials and Optoelectronic Science, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan
| | - Ya-Sen Sun
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
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Hong JW, Jian YQ, Liao YP, Hung HH, Huang TY, Nelson A, Tsao IY, Wu CM, Sun YS. Distributions of Deuterated Polystyrene Chains in Perforated Layers of Blend Films of a Symmetric Polystyrene -block-poly(methyl methacrylate). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:13046-13058. [PMID: 34696591 DOI: 10.1021/acs.langmuir.1c02132] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We have examined the spatial distributions of polymer chains in blend films of weakly segregated polystyrene-block-poly(methyl methacrylate) [P(S-b-MMA)] and deuterated polystyrene (dPS). By fine-tuning the composition (ϕPS+dPS = 63.8 vol %) of the total PS/dPS component and annealing temperature (230 and 270 °C), P(S-b-MMA)/dPS blend films mainly form perforated layers with a parallel orientation (hereafter PLs//). The distributions of dPS in PLs// were probed by grazing-incidence small-angle neutron scattering (GISANS) and time-of-flight neutron reflectivity (ToF-NR). GISANS and ToF-NR results offer evidence that dPS chains preferentially locate at the free surface and within the PS layers for blend films that were annealed at 230 °C. Upon annealing at 270 °C, dPS chains distribute within PS layers and perforated PMMA layers. Nevertheless, dPS chains still retain a surface preference for thin films. In contrast, such surface segregation of dPS chains is prohibited for thick films when annealed at 270 °C.
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Affiliation(s)
- Jia-Wen Hong
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Yi-Qing Jian
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Yin-Ping Liao
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Hsiang-Ho Hung
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Tzu-Yen Huang
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Andrew Nelson
- Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - I-Yu Tsao
- Institute of Materials Science and Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Chun-Ming Wu
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Ya-Sen Sun
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
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